Dec 15, 2020 - Energy & Environment

Study finds viable pathways to "net-zero" U.S. emissions by 2050

Smokestacks and red sky
The gas-powered Valley Generating Station in the San Fernando Valley on March 10, 2017. Photo: David McNew/Getty Images

A major Princeton University-led analysis concludes there's a range of economically beneficial and technologically feasible options for reaching "net-zero" U.S. greenhouse gas emissions by 2050 — but big investments and supportive policies would need to begin now.

The big picture: President-elect Joe Biden has embedded that 2050 target in his plan, and a number of states and major corporations share that goal or similar ones. More broadly, net-zero emissions by midcentury is considered a global goal for avoiding some of the most damaging effects of climate change.

Why it matters: Setting top-line targets, which is very popular these days, is very different from actually creating viable ways to meet them.

  • The study offers highly granular analysis of the technologies and deployment pathways that could transform top-line targets to on-the-ground changes to the U.S. energy system in different regions.

How it works: The researchers modeled a range of pathways that involve varying levels of renewable power increases, building and vehicle electrification, bioenergy, carbon capture and storage, nuclear energy, enhanced carbon "land sinks" via better forest and farm practices, and more.

  • They conclude that all of the pathways result in net energy-sector employment increases and benefit public health by cutting air pollution.

Yes, but: None of this is easy at all. The study notes it would require unprecedented rates of deployment of a slew of technologies.

  • The analysis envisions $2.5 trillion in "additional capital investment into energy supply, industry, buildings, and vehicles over the next decade relative to business as usual."
  • However, the researchers find that "total annualized U.S. energy expenditures would increase by less than 3% over 2021-2030."

What's next: While the options ultimately involve a range of technology mixes, the study finds common near-term — and ambitious — "priority actions" between now and 2030 that would help regardless of the ultimate trajectory.

They include:

  • 50 million electric vehicles on U.S. roads and several million public charging stations nationwide.
  • More than doubling the share of electric heat pumps in homes to reach around 23%, and tripling their use in commercial buildings.
  • Huge growth in wind and solar-generating capacity, accompanied by a roughly 60% expansion of high-voltage transmission capacity.
  • Begin building out a nationwide CO2 transportation and underground storage basins.
  • Investing in a suite of less mature technologies that could be significantly scaled up after 2030, such as CO2 capture in a range of industries, hydrogen and synthetic fuel production from clean power sources, next-wave bioenergy crops, direct air capture and more.

The bottom line: The 2050 target is achievable and affordable with "proactive policy and action," said Princeton University assistant professor Jesse Jenkins, a co-author of the study.

  • Jenkins said that in the 2020s alone, it would save tens of thousands of lives and create at least a half-million new jobs.
  • The study sees hundreds of thousands of premature deaths potentially being avoided over the next 30 years thanks to reductions in air pollution, including fine particulate matter.
Go deeper